On Tue, Oct 23, 2012 at 4:49 PM, IVP wrote: > > And scanning with an X-Y plotter.... And a single pixel pickup... > > 600mm /0.5mm =3D 1200 passes... at even 1 ms per pixel that's like > > 24 minutes of scanning... > > > > your application must be... Interesting :-) > > Well, that's two of us who think it might be ;-) > > It's part of an idea suggested a while back about burning cutting > patterns onto wood with a laser, primarily for fine bandsawing or > scrollsawing > > The universal method presently is to print out the pattern and stick > the paper to the wood with contact adhesive. Cut the wood and > then remove the paper. It's quick, but glueing is a bit invasive and > can cause staining, plus you've got more sanding > > The idea I'm trying is to scan the pattern, store the image, and then > play it back through a burner. Either that or have two X-Y tables, > one for reading, one for burning, just like you'd copy a CD, with > no intermediate storage. Although it's very easy to store a file so > not adding an SRAM would be short-sighted > > I've tried it non-mechanically and it's certainly very doable, if slow. > For what I have set up here that's mostly due to the burning speed > of the laser. I am considering a small router with a fine bit to do > the drawing, pretty much a basic 2D CNC, but of course you'd > have to make sure any routing is done outside the line and that > would take s/w a little smarter than simple lines. Plus the size of the > bit (1.8mm I think is the smallest commonest carbide) limits the > resolution, but you'd pick the right jobs to use it on > > Woodworkers are a mellow laid-back bunch. Even if a scan and > burn took an hour, that time can be spent on many other things in > the workshop, especially once you have the first item to work on > > Joe > -- > Ok, interesting was the right adjective.. :-) Some random thoughts... If you want really small carbide router bits, the PCB industry uses some down in the 0.020" range (about 0.5mm) What you've described is basically a raster scanning operation, but, I'd expect your laser marker/burner to execute vector moves (raster is certainly possible... single pixel dot matrix...) that's a non-trivial bit of conversion math. Aside from the math, what you described above is about 1.5 Mpixels.. And storing multiple "scans".. The whole thing suggests PC to me. A second hand PC, cheap web cam on a stand with a good light, Inkscape and some of the available plugins and you're about there. Though I freely admit, I've used some "highly unconventional" solutions before when the journey was more important than the destination. :-) -Denny --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .